Coming off priventing device of a joint of an air supply and exhaust pipe

ABSTRACT

The present invention is a coming off preventing device of joining part of an air supply and exhaust pipe which joins by inserting an entry  3  of the air supply and exhaust pipe into a socket  2  of the air supply and exhaust pipe which comprises, providing a cut out window  9  at said socket side, a metal stopper  4  is equipped at the outer side of the cut out window, said metal stopper  4  forms a push part  5  on an upper surface of one end, a rectangular shape lock part  12  on a lower surface of another end and a bearing  13  on an upper surface of center part, further a lock parts  10  to lower surface of which one end of a plate spring  14  bended to have obtuse angle is welded, a joint cover  11  which covers said lock parts  10  and fixes said lock parts by axial, further, to the entry side, a circumferential groove  7  which stops coming off by fitting the rectangular shape lock part of said lock parts in it is engraved to the opposite direction to the entry with gradient, and an entry stopper  8.    
     By only inserting an entry  3  into a socket  2,  a lock part  12  is fixed into a circumferential groove  7  and a coming off preventing function acts, further only by pushing a push part  5  by a finger, an air supply and exhaust pipe can be easily pulled off from another air supply and exhaust pipe.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a coming off preventing device of a joining part which joints an air supply and exhaust pipe by inserting an entry of other air supply and exhaust pipe to a socket of the air supply and exhaust pipe. More in detail, the present invention relates to a coming off preventing device of a joining part of an air supply and exhaust pipe characterizing having a coming off preventing effect when jointed by inserting the entry to the socket and can be pulled out at a touch.

2. Description of the Prior Art

Piping of an air supply and exhaust pipe of a combustion apparatus is carried out by joining air supply and exhaust pipes by inserting an entry of the air supply and exhaust pipe to a socket of another air supply and exhaust pipe. At the piping, a coming off preventing device is equipped to each air supply and exhaust pipe not to coming off the entry from the socket at the joining part. Conventionally, these kinds of coming off preventing device uses an apparatus having a structural feature characterizing that an elastic pawl plate is equipped to inner surface of a socket facing toward inner direction and said elastic pawl plate is fitted in a circumferential groove engraved in an entry when the entry is inserted to the prescribed position of the socket (JPH10-253038 Publication, JP2000-146066 Publication). This coming off preventing device has a problem that stable strength against pulling out forth can not be obtained, further has a problem of complicated handling for pulling out, because, at the pulling out of an inner pipe from an outer pipe, it is necessary to rotate the inner pipe or the outer pipe so as the elastic pawl plate to meet to a pull out groove engraved beside the circumferential groove.

Therefore, a device characterizing a coming off preventing function acts only by inserting an entry to a socket and become possible not to pull out after inserted, and when it become necessary to pull off, it makes possible to pull off at a touch without rotating an air supply and exhaust pipe is proposed. For example, a coming off preventing device mentioned below is proposed in JP2000-304182 Publication. Namely, a cut out window is provided at a socket, a cover in which a flank space, a lock wall and a slide guide part are formed is equipped at the outer side of the cut out window, a lock parts providing a lock part on one end and a stopper manipulation part on another end is contained in the cover by maintaining a center part with said slide guide part, while, to the entry side, a circumferential groove which stops coming off by fitting the lock part of said lock parts in it when the socket is inserted to the prescribed position is engraved.

OBJECT OF THE INVENTION

The object of the present invention is to provide a joining apparatus characterizing a coming off preventing function acts only by inserting an entry to a socket and maintains stable strength against pulling out forth when inserted, further when it become necessary to pull off, it makes possible to pull off at a touch.

DISCLOSURE OF THE INVENTION

The present invention is a coming off preventing device of a joining part of an air supply and exhaust pipe which joins air supply and exhaust pipes by inserting an entry of one air supply and exhaust pipe into a socket of another air supply and exhaust pipe which comprises, providing a cut out window at said socket side, a metal stopper (stopper fittings) is equipped at the outer side of the cut out window, said metal stopper forms a push part on an upper surface of one end, a rectangular shape lock part on a lower surface of another end and a bearing on an upper surface of center part, further a lock parts to lower surface of which one end of a plate spring bended to have obtuse angle is welded, a joint cover which covers said lock parts and fixes said lock parts by axial, further, to the entry side, a circumferential groove which stops coming off by fitting the rectangular shape lock part of said lock parts in it is engraved to the opposite direction to the entry with gradient and an entry stopper. It is desirable that said rectangular shape lock part is of square shape. Further, it is desirable to equip an O ring behind said metal stopper.

EFFECT OF THE INVENTION

The coming off preventing device of a joining part of an air supply and exhaust pipe of the present invention is characterized that coming off preventing function acts only by inserting an entry of an inner pipe to a socket of an outer end, therefore preventing function to pull out is displayed by stable strength after inserted. Further, when it become necessary to pull out the jointed pipe, since it is possible to pull out at a touch, this device is excellent in easy handling.

BRIEF ILLUSTRATION OF THE DRAWING

FIG. 1 is a prospective view of the coming off preventing device of joining part of an air supply and exhaust pipe of the present invention.

FIG. 2 is a cross sectional view of a socket side of coming off preventing device of joining part of an air supply and exhaust pipe of the present invention.

FIG. 3 is a cross sectional view of a lock parts of the device of the present invention.

FIG. 4 is a cross sectional view of a socket side of an air supply and exhaust pipe before joining of other example of the present invention.

FIG. 5 is a cross sectional view of an entry of an air supply and exhaust pipe before joining of the present invention.

FIG. 6 is a cross sectional view of a joining part after joining of the present invention.

DESCRIPTION OF THE PREFERRED EMBODYMENT

The Example of the present invention will be illustrated according to drawings. In general, an air supply and exhaust pipe has a certain length, and a socket is provided on one end and an entry is provided on another end. In the case to lay a pipe using said air supply and exhaust pipe, pipes are joined by inserting an entry to a socket of the air supply and exhaust pipe. FIG. 1 is a perspective view illustrating a joining process of the air supply and exhaust pipe equipping the coming off preventing device of a joining part of the present invention. 1 and 1′ are an air supply and exhaust pipe, 2 is a socket provided to the air supply and exhaust pipe 1. 3 is an entry provided to other air supply and exhaust pipe 1′. 4 is a metal stopper. The metal stopper is equipped to the outer side of a cut out window provided to the socket 2. 5 is a push part. 6 is an O ring container provided to the part of the metal stopper. Further, 7 is a circumferential groove engraved to the entry 3, and 8 is an entry stopper. 19 is a hole to fit in a pin. By inserting an entry 3 of an air supply and exhaust pipe 1′ to the socket 2 of the air supply and exhaust pipe 1, the air supply and exhaust pipe 1 and the air supply and exhaust pipe 1′ is jointed. The shape of the air supply and exhaust pipe can be linear shape or curved shape. Further, the present invention can be applied to a joining part of an air supply and exhaust pipe to which only a socket is provided and an air supply and exhaust pipe to which only an entry is provided.

FIG. 2 is a cross sectional view of the socket 2 of the air supply and exhaust pipe 1. 9 is a cut out window provided to the socket 2 of the air supply and exhaust pipe 1. A metal stopper 4 is composed of a lock parts 10 and a joint cover 11 which covers the lock part 10. FIG. 3 is a cross sectional view of the lock part 10. This lock part 10 has a push part 5 on the upper surface of one end, a lock part 12 of rectangular shape on the lower surface of the other end and a bearing part 13 on the outer surface of the center part and a plate spring 14 bended to have obtuse angle is welded on a lower surface side. A lock parts 10 is desirable to be one long metal plate processed by bending and to form a push part 5, a bearing part 13 and a lock part 12. In the process, the push part 5 is processed to have a shape so as to be easily pushed by a finger. The bearing part 13 has a space in which a pin can be inserted so as to permit voluntary rotation. The lock part 12 is bended to form rectangular shape. In this example, forms a square shape cross sectional view. Further, the plate spring 14 is composed of a long plate spring and bended to have an obtuse angle. By bending to have an obtuse angle, the spring function of the plate spring can be effectively displayed. One end of the plate spring 14 is adhered by a method for example by welding to the lock parts 10. It is desirable to bend other end of the plate spring which is spot welded to have an obtuse angle to the opposite direction. 15 is a spot welded part.

In FIG. 2, a joint cover 11 covers a lock parts 10 and has an enough space so that a lock part 12 of the lock parts 10 moves to upper and lower position. Further, to the joint cover 11, a cut out window 18 which makes thrust out the push part 5 of the lock parts 10 is provided. And to the joint cover 11, a hole 19 to fix in a pin 16 is punched. Said pin is thrust in the bearing part 13 of the lock parts 10 so as to rotate freely, and both ends of the pin 16 are fixed in holes 19 punched right side and left side of the joint cover 11. By said structural feature, the lock parts 10 is supported by pin 16 in a condition that the free rotation around axis of pin 16 is possible. That is, the lock parts 10 is fixed to the joint cover 11. Further, in this example, one end of plate spring 14 is spot welded closely to the lock part 12 locating to the lower surface between the lock part 12 of the lock parts 10 and the bearing part 13. Further, one end of plate spring 14 can be spot welded to the lower surface between the push part 5 of the lock parts 10 and the bearing part 13 closely to the push part 5, as shown in FIG. 4.

A metal stopper 4 is equipped at the condition when a lock part 12 of a lock parts 10 is projecting to the inner side from the cut out window 9 formed to the socket 2 side of an air supply and exhaust pipe 1, and a push part 5 is projected from a cut out window 18 of a joint cover 11 and an end of plate spring 14 of the lock parts 10 (end which is not spot welded) is contacted to the outer surface of the air supply and exhaust pipe 1 (state of FIG. 2 or FIG. 4). Equipping of the metal stopper 4 is carried out by fixing the outer periphery part of a joint cover 11 to prescribed position by spot welding. Further, it is desirable to provide an O ring to seal a joining part closely to the behind of the metal stopper 4. 17 is an O ring and 6 is a container of the O ring.

FIG. 5 is a cross sectional view of a socket of an air supply and exhaust pipe 1′. 7 is a circumferential groove. This circumferential groove 7 has an enough depth to fix in a lock part 12 of a lock parts 10 when connected. Further, said circumferential groove 7 is formed so as to have an inclination to the opposite direction of a socket. That is, opposite side of the socket of the circumferential groove 7 is inclined to the outer dimension. By forming as above, since clearance is formed when a lock part 12 of lock parts 12 is fixed in the circumferential groove 7, fine adjustment of laying pipe becomes easy and can cope with thermal expansion of an air supply and exhaust pipe. 8 is an entry stopper, which is formed a convex part having arc shape along with the circumference of the air supply and exhaust pipe 1′. When an entry 3 of an air supply and exhaust pipe 1′ is inserted into a socket 2 of an air supply and exhaust pipe 1, an end of the socket 2 is contacted to the convex part of the entry stopper 8 and further inserting beyond the position becomes impossible. Further, by providing said entry stopper 8, it becomes possible to enhance the pipe strength of the socket 3 and protects from breaking.

FIG. 6 is a cross sectional view illustrating a state that an air supply and exhaust pipe 1 and an air supply and exhaust pipe 1′ are joined by inserting an entry 3 of an air supply and exhaust pipe 1′ shown in FIG. 5 into a socket 2 of an air supply and exhaust pipe 1 shown in FIG. 2. When the entry 3 is of the air supply and exhaust pipe 1′ is inserted into the socket 2 of the air supply and exhaust pipe 1, a rectangular lock part 12 of a lock parts 10 is pushed up by outer wall of the entry 3 of the air supply and exhaust pipe 1′, however, the stress to push down by action of a spring plate 14 is always loaded to the lock part 12. Consequently, when the insertion is progressed further, and a circumferential 7 provided to the entry 3 of the air supply and exhaust pipe 1′ is reached to the position of lock part 12 of the lock part 10, the lock part 12 is pushed down and fixed in circumferential groove 7. An end of entry 2 of the air supply and exhaust pipe 1 contacts to the socket stopper 8. Accordingly, the joining of an air supply and exhaust pipe with another air supply and exhaust pipe can be carried out without coming off of the air supply and exhaust pipe from another air supply and exhaust pipe and without excess insertion of the air supply and exhaust pipe.

In case to pull off the entry 3 from the socket 2 of an air supply and exhaust pipe 1, the push part 5 projected from the metal stopper 4 is pushed down by a finger. By pushing down by a finger, a lock part 12 of a lock parts 10 is lifted around a axis of a pin 16 and comes off from a circumferential groove 7 of the entry 3. Accordingly, the entry 3 of the air supply and exhaust pipe 1′ can be easily pulled off from the socket 2 of the air supply and exhaust pipe 1. 

1. A coming off preventing device of a joining part of an air supply and exhaust pipe which joins air supply and exhaust pipes by inserting an entry of one air supply and exhaust pipe into a socket of another air supply and exhaust pipe which comprises, providing a cut out window at said socket side, a metal stopper is equipped at the outer side of the cut out window, said metal stopper forms a push part on an upper surface of one end, a rectangular shape lock part on a lower surface of another end and a bearing part on an upper surface of center part, further a lock parts to lower surface of which one end of a plate spring bended to have obtuse angle is welded, a joint cover which covers said lock parts and fixes said lock parts by axial, further, to the entry side, a circumferential groove which stops coming off by fitting the rectangular shape lock part of said lock parts in it is engraved to the opposite direction to the entry with gradient and an entry stopper.
 2. The coming off preventing device of joining part of an air supply and exhaust pipe of claim 1, wherein a rectangular shape lock part is a square shape.
 3. The coming off preventing device of joining part of an air supply and exhaust pipe of claim 1 wherein one end of plate spring is welded to the lower surface between a lock part of a lock parts and a bearing part.
 4. The coming off preventing device of joining part of an air supply and exhaust pipe of claim 1 wherein one end of plate spring is welded to the lower surface between a push part of a lock parts and a bearing part.
 5. The coming off preventing device of joining part of an air supply and exhaust pipe according to claim 1 wherein an O ring is equipped behind a metal stopper. 